Nail feeding mechanism



Oct. 10, 1939, H. PAxToN `NAIL FEEDING MECHANISM Filed Feb.v 1,I 1937 oct. 10, 1939. H .PAXTON 2,175,482

NAIL FEEDING MECHANISM Filed Feb. l, 193'? 2 Sheets-*Sheet 2 /34 /35 IHHHIII.,

Patented Oct. 10, 1939 UNITED STATES PATENT FFECE Machinery Corporation,

San Jose, Calif., a

corporation of Delaware Application February 1,

11 Claims.

This invention relates to nail handling apparatus and is particularly useful in the feeding of nails to a nailing machine.

In nailing machines the driving of nails into the work is generally accomplished in a certain sequence in accordance with the requirements of the work.

It is an object of this invention to provide a means for feeding nails intermittently to certain chucks of a nailing machine in accordance with the requirements of that portion of the work served by these chucks.

One of the methods long in use for manufacturing boxes in a box making machine has been to provide therein means for supporting the box ends, and a center partition if required, and to rotate these ends and partition after each of three successive nailing operations during which two sides and bottom of the box are nailed onto the ends and the partition. In the making of lemon boxes by this method, for instance, by a full automatic machine such as shown in U. S. Letters Patent No. 1,844,333 issued to E. C. Northrup on February 9, 1932, a battery of seven nail chucks are provided in the nailing mechanism over each of the box ends and the center partition. As the sides of a lemon box are narrower than the bottom and therefore require only six nails whereas the bottom requires seven nails, it is desired that only sixV of the seven chucks in each of these batteries be supplied with nails when a side of the box is being nailed thereon but that all seven chucks be provided with nails when the bottom of the box is being nailed on so that seven nails will be driven through the bottom of the box into each of the box ends and into the center partition. While many different devices have been designed for the intermittent feeding of nails to the seven chucks in these batteries so that these seven chucks will be supplied with. nails only during the nailing of the bottom on the box, these devices have all been relatively complex in construction and operation and correspondingly subject to disorder.

It is an object of this invention to provide a relatively simple and positive mechanism for feeding nails to nail chucks in a box makingv machine only during certain of a series of nailing operations.

The manner of accomplishing the foregoing objects as well as further objects and advantages will be made manifest in the following description taken in connection with the Vaccompanying drawings, in which:

Fig. l is a fragmentary front elevational view 1937, Serial No. 123,409

of a box nailing machine as shown in the aforementioned patent, this view illustrating a preferred embodiment of the invention incorporated with said machine.

Fig. 2 is a fragmentary enlarged plan view taken on the line 2--2 of Fig. 1 with certain portions thereof broken away to illustrate the construction of the invention.

Fig. 3 is an enlarged cross sectional view taken on the line 3-3 of Fig. 2 and illustrating one of the gates of my invention in position for blocking the feeding of nails.

Fig. 4 is an enlarged fragmentary detail view illustrating the master bar of my invention as it is disposed during a nailing operation of the nailing machine.

Fig. 5 is a view similar to Fig. 4 showing the master bar in a position as during the interval between nailing operations.

Fig. 6 is a view similar to Fig. 4 but illustrating the gate control bar of the invention in gate opening position.

Fig. 7I is an enlarged fragmentary plan view of the right-hand portion of Fig. 2 with the gate bar shown in gate opening position.

Wherever possible the elements shown in the drawings that belong to the prior art will be identified by the same reference characters as indicate these elements in the specification of the Northrup patent aforementioned. It is thus to be noted that the nailing machine N includes a frame 2. Slidable vertically on this frame is a nail driver cross head 3l carrying three brackets 62, from each of which extends downwardly seven nail drivers 6U. Slidable vertically in suitable bearings provided on the cross head 3| are shafts 'I3 upon the lower ends of which are mounted brackets 55, these brackets carrying three batteries of nail chucks I6 seven chucks in each batery. Each of these chucks is disposed in vertical alignment with and slidably receives one of the nail drivers 69. The upper ends of the vertical slide shafts 13 are provided with a cup supporting bar l2 on which are supported twentyone nail cups 1I which are connected by the usual nail pipes 1U to the chucks I6.

As shown in the aforesaid patent, a suitable means is provided for positioning the box ends and center partition beneath the batteries of chucks I6, for feeding side and bottom slats onto these ends and partition for lowering the cross head 3i and all the structure mounted with the chucks I6 on the vertical shafts 13 so that the chucks are brought to rest o-n the work and the cross head 3l then continues down to push the nail drivers 60 entirely into the chucks |6 and drive the nails from these chucks into the work. At the conclusion of each such nailing operation the cross head 3| and chuck means are lifted from the work and the latter rotated 90 as already mentioned preparatory to the performing of the next nailing operation thereon.

Between successive nailing operations nails are fed into the cups 1| and these 4gravitate immediately down the tubes' 10 into chucks I6. Mounted on the upper end of the frame 2 for the purpose of supplying these nails to nail cups 1| is an automatic nail feeding and selecting apparatus 5. This apparatus includes the preferred embodiment of the present invention illustrated in the drawings, and comprises a nail hopper which is pivoted on the frame 2 adjacent its forward lower edge |3| and rocks about said edge to feed nails through a series of openings |32 in the forward wall |33 of said hopper. The nails thus fed slide downwardly in vertical slots |34 provided centrally in a series of nail runs |35, one of which is provided for each of the cups 1 I -andterminated at its lower end just to one side of the center of this cup.

Slidable in bearings |40 and |4| (Fig. 2) on the frame 2 is a master pick bar |42 having a stop shoulder |43 which tends-to be held against the bearing |40 by a contractile spring |45. Provided on the right-hand end of the bar |42 is a cap screw |41 which rides in a vertical notch (Fig. l) in the upper end of a'cam lever |48, the latter having a cam face |49 on its lower end. Provided on the cross head Y3| isa cam roller |50 which engages the cam face |49 ofthe lever |48 each time the cross head 3| rises-following the completion of a `nailing operation so as to swing the lever |48 and tip master bar |42 towards the left to separate the-shoulder |43 from the bearing |40 as shown in Figs. 1 and 2.

Secured on the upper face of thebar |42 is a series of nail picks |55, each of'these nail picks having a straight edge |56 4which is broken in a left-hand portion thereof by a nail picking notch |51, the edge |56 being parallelwith the bar |42 and disposed very close to themouth of the guide slot |34 of one of the nail runs`l35. When the bar `|42 is in its rightward position as shown in Figs'. .4, 6 and '1.the notches 4|51 are in correct alignment with the guideways |34 and allow sufiicient room for a nail to be fed from the ends of these guideways into the notches |51. When the bar 42 is in its leftwardmost position as shown in Figs. l, 2 and 5, the unbroken portions ofthe edgesl of the nail picks |55 aredisposed opposite .the lower ends of the nail guideways |34 so as to prevent the feedingof any nails from these guideways while at the same time the notches' |51 have been moved to the leftward, as shown in Fig. 2, so that any nails which have been previously fed into these notches while the latter were opposite Vthe guideways '|34 are now discharged downwardly by gravity into the cups 1| disposed therebeneath.

Secured loosely in place on the top of the slide bearing |40 by two screws |60 and |6| `and a spring |62 coiled about thelatter is a yieldable pawl |63. This pawl is adapted to` engage teeth |64 of a ratchet wheel |65 which is rotatably mounted on the -end ofthe .bar |42 beyond the shoulder |43 `so as to rotate .under a degree of friction which prevents its being turned acci* dentally. Extending rearwardly from the ratchet Wheel |65 is a series of pins |10, these being equally spaced about the wheel and of a number one third as great as the number of ratchet teeth |64. During each reciprocation of the bar |42 the dog |53 engages one of the teeth |64 and rotates the wheel |65 one-twelfth of a revolution or the circumferential distance of one tooth. At the completion of every third one of these partial revolutions of the wheel |65, one of the pins |10 is placed so that it lies on the right-hand side of the wheel |65 and in the same horizontal plane with the axis of the latter and remains in this position as the bar |42 returns its rightward position.

As shown in Figs. 2 and '1, the bearings |46 and Y|4| have horizontal bores for receiving slide pins |80 and |8 the bore for the latter being counter- Abored to receive a compression spring |82 disposed about the pin |8|. These pins |80 and |8| have brackets |84 and |85 at their inner ends which are xed to opposite ends of a gate supporting bar |90 which is relatively at and lies against the rear face of the master pick bar |42.

As shown in Fig. 3, the rear face of the gate mounting bar |90 is disposed just forwardly of the deepest portions of the nail picking notches |51. There is thus a free space |9| between the rear face ofthe Vbar |90 and the lower end of each of thenail runs which permits the lowermost nail |92 of a column of these in that nail run to feed downwardly into the notch |51 disposed opposite the guideway |34 of this nail run Whenever the space |9| is unobstructed.

Asshownin Fig. 1, the nail runs |35 and the cups into which nails are delivered from these nail runs are divided .intothree groups of seven each, each of these groups delivering nails to the chucks vmounted on one of thebrackets 55. One of the-nail runs l|35 cf-each of these groups of seven supplies vnails-for the forwardrnost chuck |6 on the bracket 55 disposed therebeneath. These threelnailruns will hereinafter be referred to specificallyas nail runs' R.

Welded onto the rear face of the gate supporting bar l|90 are three nail `gates |95, each of these being-disposed inone of the free spaces |9| oppositeoneof thenail runs R when the bar |90 is disposed in its leftward position as shown in Figs. 2, 3, 4and 5.

,Operation As alreadypointedouuthe machine N operatesto assemble boxes by automatically repeating a seriesuof three4 nailing operations, in the rst of which one side is nailed onto the box, in the second of Whichthe bottom `is `nailed onto the box and-inthe third of which the other side is nailed onto the box. Each of these nailing operations is effected bya `reciprocatory downward and upward movement of the cross khead 3| and the parts assembled thereon, each of these movements beginning and ending with said cross head and its assembled'parts positioned as shown in Fig. `1. During the rising `of the cross bar 3| in each of these nailing operations the roller |50 engages the lever |48 and shifts the master pick bar |42 to its leftwardvposition as shown in this ligure where it remains during the intervals between successive nailing 'operations andwhen the -machine is at rest. When-the cross head '3| moves downwardly inf-initiating each nailingoperation the lever |48 is released from restraint by the roller so that the spring |45 pulls'the bar |42 into its rightward position in which it is shown inrFigspl, 6 and 7.

VThe gate supporting `bar |90 remains in the positionin which it is shown in Figs. 2, 3, 4 and 5 excepting when it is shifted to the right by the engagement .ofone of the pins |10 with the pin during a return of the bar |42 from the leftward position of the latter to its rightward position. Such an engagement takes place during the downward movement of the nailing cross head 3| incidental to each third nailing opera tion carried on in the machine N. 'I'his intermittent character of the actuation of the control supporting bar results from the fact that the bar |42 must be reciprocated from its rightward to its leftward position three times to cause the rotation of the ratchet wheel |65 one quarter of a vrevolution so as to bring one of the pins |10 into position at the right side of this ratchet Wheel and lying in the plane of the axisof the wheel. The arrival of a pin |10 in this position is illustrated in Fig. 5 where it is seen thatY this takes place as the bar |42 is shifted into its leftward position during the third of a series of three reciprocations following the last previous reciprocation in which another of the pins |10 had been placed in a similar position. When a pinllii is thus disposed it is in alignment with the pin |80 and will shift the bar i90 to the right as shown in Figs. 6 and 7 when the bar |42 returns :to the right. This .results in the gates being shifted out of the spaces |0| opposite the lower ends of the nail runs R so that immediately upon the arrival of the notches |51 of the picks |55 in alignment with the guideways |34 of the nail runs R, the foremost nails in these runways will be delivered into these notches and upon the left Ward movement of the master bar |42, which immediately follows, the nails thus fed into the notches |51 last above mentioned will be delivered through the respective cups 1| and tubes 10 therebelow to the three forwardmost nail chucks |6 in the machine. As the nails driven from the chucks |6 during a given nailing operation are always fed to these chucks during the last'preceding nailing operation, the ratchet wheel |65 is set so as to cause a feeding of nails as just described hereinabove to the foremost of the nail chucks I6 during the nailing operation which applies the first of the sides to the box. All of the seven chucks in each of the three banks thereof are thus supplied with nails during the nailing of the bottom onto the box so that the bottom is secured to each of the box ends and the middle partition by seven nails instead of six as is the case with both sides.

With the return of the master pick bar |42 to its leftward position in the accomplishing of the feeding of nails from all of the nail runs |35 to all of the chucks |6, the pressure of the pin |10 against the pin |80 is released permitting the bar |90 to be returned by the spring |82 to its leftwardmost position in which the gates |95 again block the delivery of nails from the nail runs R and in which positions these gates remain during the two nailing operations immediately following. As the shifting of the gate supporting bar |90 to the rightward is effected by the rightward movement of the master pick bar |42 which is in turn caused by the spring |45, it is clear that the latter spring is considerably stronger than the spring |82 on the gate supporting bar pin |8| which must be overcome in order to move the bar |90 to the right.

While I have shown and described my invention as applied to the particular purpose of controlling the feeding of nails intermittently to the various chucks of an automatic box nailing machine, it is to be understood that the invention has a much broader application and may be used for numerous other purposes in the intermittent feeding of nails or other similar elements.-

What I claim is: 1. In a nail feeding mechanism, the combination of a plurality of nail runs; a plurality of nail picks, each of which is for picking nails one at a time from one of said nail runs; unitar-g means for actuating said nail picks simultaneu ously at recurrent intervals to pick nails from saidruns; means continually positioned in blocking relation with the foremost nail in certain of said nail runs and thereby preventing the delivery of said foremost nails so blocked to those nail picks provided for picking said foremost nailsyand means operative to remove said blocking means from blocking position just prior to a nail picking operation and return said blocking means to blocking position immediately following said nail picking operation, said blocking means remaining in blocking position except when thus temporarilykremoved therefrom asY aforesaid.

2. In a nail feeding mechanism, the combination of: a plurality of nailV runs, the delivery mouthsV of which lie in a given line; nail pick means which lies parallel to said line and which is adapted when shifted axially to pick the foremost nail from each of said runs; block means lying parallel with said line and adapted to be shifted axially to move into and from a blocking position in which said block means prevents the delivery of certain of said foremost nails to said nail pick means; and means for co-ordinately actuating said nail pick means and said block means to cause said blocking action to reoccur at predetermined intervals in a series of operations of said nail pick means.

3. In a nail feeding mechanism, the combina.- tion of a plurality of nail runs, the delivery mouths of which are disposed along a given line; a nail pick bar mounted close to and parallel with said line and shiftable axially; nail picks on said bar which 4are adapted to pick the foremost nail from each of said run-ways when said bar is shifted axially as aforesaid; a block bar disposed adjacent said line .and parallel thereto and mounted so as to be shiftable axially; block means on said block bar adapted to be shifted into and from blocking position by the shifting of said block bar, said block means when in blocking position preventing the delivery of certain of the foremost nails of said nail runs to the nail picks provided for receiving these; and means for coordinately shifting said nail pick bar .and said block bar axially to perform a series of nail picking operations in which said blocking action reoccurs at predetermined intervals.

4. In a nail feeding mechanism, the combination of a plurality of nail runs; a plurality of nail picks, each of Which is for picking nails one at a time fro-m one of sai-d nail runs; block means for preventing the delivery of nails from certain of said nail runs to their respective picks when the latter are actuated to receive such nails; and a member extending across said nail runs adjacent the discharge ends of said nail runs, said block means being mounted on said member and controlled by the latter to render said block means operative as aforesaid during certain of a series of actuations of said nail picks.

5. A combination as in claim 4, in which said block means are substantially integral with said member and partake of the movement of the latter in order to effect control through said member of said block means.

6. In a nail feeding mechanism, the combination of: a plurality of nail runs; a plurality of. nail picks, each of which is for picking nails one at a time from one of said nail runs; a nail pick bar on which said nail picks are mounted and .adapted to be actuated by axial movement of said bar; and means lying substantially between said bar and the discharge ends of said nail runs and parallel with said bar and operative co-ordinately With said bar to prevent the delivery of nailsfrom certain of said nail runs to their respective picks when the latter are actuated to receive such nails.

7. A combination as in claim 6, in which said delivery prevention means is actuated by being shifted in a direction parallel with the axis of said. bar.

8. A combination as in claim 6, in which said delivery prevention means is actuated by being shifted in a direction parallel with the axis of said bar and in which means is provided for actuating said delivery prevention means from said bar.

9. In a nail feeding mechanism, the combination of: a plurality of nail runs with the discharge mouths thereof disposed along a given line; a

picker bar disposed parallel with said line in front of said mouths, said bar being slidable longitudinally; a plurality of nail picks provided on said bar for picking nails one at a time from each of said nail runs; means for recurrently reciprocating said bar to effect said nail picking operation; a member disposed adjacent to` said bar and slidable longitudinally between blocking and nonblocking positions; blocks provided on said member and adapted when the latter is in blocking position to prevent the discharge of certain of the foremost nails in said nail runs by the nail picks positioned to receive said nails; and a mechanism operable by said reciprocations of said bar to actuate and shift said member longitudinally into its non-blocking position as aforesaid, said shifting taking place during certain of the reciprocations of said bar and not during others.

10. A combination as in claim 9', in which said member lies against and slides upon said bar.

11. A combination as in claim 9, in which said member lies against and slides against said bar and is disposed between said bar and the aforesaid mouths of said nail runs.

HALE PAXTON. 

